Automatic regulator for electric distribution



1N0 Model.)

W. STANLEY, Jr.

AUTOMATIU' REGULATOR FOR ELEGTRIU DISTRIBUTION.

No. 366,523. Patented July 12,1887.

wi/bneooao N, PETERS, PhOlO L'vthngnpher. Wlihingkm. D. C.

UNITED STATES PATENT ()FFICE.

WILLIAM STANLEY, JR, OF GREAT BARRI NGTON, MASS ACHUSETTS, ASSIGNOR TO GEORGE WESTINGHOUSE, JR.,

OF PITTSBURG, PENNSYLVANIA.

AUTOMATIC REGULATOR Po- R ELECTRIC DISTRIBUTION.

SPECIFICATION forming part of Letters Patent No. 366,523, dated July 12, 1887.

Application filed November 14, 1885. Serial No. 182,844. (No model.)

and are there made to pass through the primary circuit of one or more induction-coils'or inductoriums, while the currents induced in the secondary circuits of said coils or inductoriums are caused to act upon translating devices-such, for-instance, asincandescing electric lamps.

In the ordinary operation of such a system as that hereinbefore described if the whole or any part of the translating devices are with drawn or removed from the secondary circuit the resistance of such circuit is altered. Such a change of resistance in the secondary circuit at once gives rise to a variation in the counter electro-motivc force developed by the action of the primary current in the primary circuit of the inductorium, hereinafter termed the converter, which is due directly to the increment or decrement of magnetization in the iron core. By this means a variation of the strength of current traversing the primary coil is effected, which in turn gives rise to a proportional variation in the electro-motive force of the induced currents in the secondary circuit. v

The object of this invention is to provide an automatic means of regulation, whereby a constant difference of potential may at all times be maintained in the secondary circuit or circuits of the apparatus irrespective of the amount of work which is being done therein, from which it results that the'mechanical energy consumed in operating the system may be materially economized.

In general terms, the invention consists in 5 an apparatus whereby a current of variable strength is caused to traverse the primary coil cf the converter and is automatically regulated through the instrumentality of the counter electro-motive force developed within the converter itself, the variations of which force are 5 5 caused by and dependent upon the variations of resistance in the secondary circuit. To accomplish this result there is included in the main or primary circuit of the apparatus an' electric generator which must be capable of producing an approximately constant electric current in a closed circuit of varying resistance, together with a regulator, which comprises one or more pairs of differential helices, normally tending to produce equal and opposite magnetisms in a soft-iron core. This is so 4 arranged as to constitute an automatic currentregulating device for the converter proper. The primary coil of the converter is placed ,in. multiple arc with one of these opposing 7o coils.

Assuming in the first instance the secondary circuit of the converter to be open, its resistance will be infinite, and hence there will be developed in the primary coil a counter electro-motive force or inductive resistance of maximum value. This will cause the primary current to traverse both the regulating-coils included in the primary circuit by reason of the inductive resistance encountered in the primary coil of the converter, which, in effect, 8o shunts one of the two normally-opposing coils of the regulator. The effect of this current upon theiron core of the converter,which issurrounded by the primary coil, will be nearly null, so that little or no effective magnetism will be developed therein. If now the circuit of the secondary coil of the converter be completed by a conductor offering a given resistance,thecounter electro-motiveforcedeveloped in the primary circuit of the converter will be correspondingly diminished. If another conductor be attached tothe secondary parallel, or in multiple arc with the first, or its re sistance in any other manner be diminished, the counter electro-niotive force of the primary 5 will necessarily be reduced in the same proportion. Now, it is essential to the successful operation of the apparatus that the difference of potential at the respective terminals of the secondary coil of the converter be maintained IOO approximately constant and this without reference'to any changes of resistance which may occur in its external circuit.

For this purpose it is necessary to correspondingly vary the effective strength of current traversing the primary circuit,which is in effect the same thing as the maintaining of a constant difference of potential between the opposite tern1inals of the primary coil. This is to a certain extent accomplished by the automatic action of the apparatus itself, for the reason that each successive decrement in the counter electro-motive force causes the primary coil to offer less and less resistance to the shunted primary current, so that, acting as it does as a shunt for one of the mainline coils, the primary coil will receive a eontinually-increasing proportion of the whole current. The moment that the normal inductive balance between the two opposing coils of the regulator is disturbed the coil preponderating over the other acts to it as a primary to a secondary coil, and vice versa, so that the value of the current shunted is not simply that due to ohms law, but, in addition, that which is due to the electro-motive force developed within the weaker coil by the inductive action of the core under the influence of the stronger one. As the actual amount of work done or energy absorbed increases in the secondary coil, the effective strength of current derived from the primary generator .must also be increased. Now, as the resistance of the shunt increases and the current is partially diverted from, the shunted regulator coil,the equilibrium between the magnetic forces developed in the iron core surrounded by these coils is disturbed and a counter eleetro-motive force is developed in these coils. If this counter electromotive force is increased, it is obvious that a higher electro-motive force must be used to force a unit of current through the primary circuit, and under the conditions hereinafter stated the primary generator automatically supplies this increase. This electro-motive force therefore varies inversely as the resistance of the primary circuit of the converter, but is directly proportionate to the work required to be done in the secondary circuit. It has been stated that the primary generator is so constructed as to maintain a constant current in its own circuit, and hence the potential maintained at the terminals of the secondary circuit will necessarily remain constant.

The accompanying drawing is a diagram illustrating an organization of circuits suitable for carrying out the invention.

Referring to the drawings, A represents a magneto or a dynamo electric generator or other convenient source of electricity. The generator is designed to transmit alternating or intermittent currents upon a main line, L, and it is constructed in any well known or suitable manner for the purpose of automatically maintaining a constant current in its external circuit under conditions of varying resistance. An alternating machine,whose fieldmagnets are supplied by a dynamo, A, and provided with any suitable system of automatic regulation, as shown at A", for instance, will be found well adapted to this purpose.

An induction apparatus, B, of suitable character, herein termed a converter, hasits primary coil B included in the primary circuit L. The secondary coil is included in asccondary circuit, Z Z", in which any desired translating devicessueh, for instance, as incandescent electric lamps D, D and D", due-may be included in multiple are, as shown in the figure. As the various translating devices are inserted or withdrawn from the secondary circuit, the resistance of the said circuit is varied, and the counter electro motive force developed in the primary circuit is also varied.

In the distribution of electric currents for various purposes in the manner hereinbefore set forth, especially for electric lighting, it is important that the difference of potential at the terminals of the secondary coil of the con vertcr shall be maintained at a constant value irrespective of any changes which may occur in the resistance of the circuit. Such variations, however, affect the counter electromotive force in the primary circuit and thus tend to vary the effecting current traversing the same, and again to cause the electro motive force developed in the secondary to be likewise varied; and even if the generator be so constructed as to force an approximately constant current through the primary, this alone will not remove the difficulty but will tend rather to augment it. It is essential, therefore, that means be provided for varying the amount of current traversing the coil B, as the resistance of the circuit Z Z is increased or decreased, or, what is in effect the same thing, for maintaining a constant difference of potential between the opposite terminals of the coil B, so that when the resistance of the second ary is reduced to its minimum a maximum current will traverse the primary coil B, and, on the other hand, when the secondary circuit is entirely open or disconnected, a minimum current will traverse the primary, while between these limits the effective strength of the current in the primary circuit shall vary in direct proportion to the resistance offered by the secondary. For this purpose two opposing coils, E and E are applied, by means of any suitable or convenient arrangement of diiferen tialwiuding, toasoft-iron core,F, and both these differential or normally-opposing coils are included in the primary or generator circuit. A current traversing both of these coils tends to develop equal and opposite polarities in the iron core, and therefore no magnetic effects whatever are developed. The conductor 1, leading from one terminal of the primary coil B, connects at a point, 2, between the two regulater-coils E and A conductor, 3, leading fromtheremainingterminaloftheprimarycoil, connects with the remaining terminal of the regulator-coil E at the point i. In this manner the primary coil 13 serves, in effect, as a shunt or bridge for the regu1ator-coil E". It

results from this that the effective strength of current traversing the regulatorcoil E is determined by the resistance offered by the coil B, and it will vary proportionately to the variations in the resistance of the last-mentioned coil. Thus, if the counter electro-motive force, sometimes called the inductive resistance, in the coil B be at its maximum, approximately the whole of the current of the primary circuit will traverse the regulator-coil Efland the resultant effect of the current in the two coils E and IE will be nearly zero or null, so that little or no magnetism will be developed in the iron core F. Thus a minimum amount of energy will be absorbed in generating the current traversing the primary circuit, and

the dynamo-generator will offer practically no mechanical resistance to its driving-motor. Assuming, now, that a single translating device-for instance, an electric lamp, D be incl uded in the circuit of the secondary, then the counter electro-motive force or inductive resistance will be correspondingly diminished in the primary coil B, and a proportionate amount of current will be diverted from the regulator-coil 13] through the coil B. This will give rise to a difference of potential be tween the terminals of the secondary coil of the converter. At the same time it will disturb the magnetic equilibrium of the core F, and a counter electro-motive force will be established in the surrounding coils, whose value will equal E=E or E=E+l lamp. The generator, by virtue of its inherent or automatic regulating capacity, immediately increases its electro-motive force, in order to maintain the strength of current in the primary circuit. A still further reduction in the resistance of the secondary circuit, (as, for instance, by the introduction in multiple arc of a second lamp, D will cause a further decrement in the counter electro-motive force of the primary B, and a still further increment in the effective strength of the current travcrsingthe primary will be occasioned. This in turn augments the counter electro-motive force in the coils E and E on account of E equaling E +2 lampsthat is, because EE is greater than before. An approximately constant difference of potential will therefore be maintained between the terminals of the primary as Well as of the secondary coils throughout the entire range of working.

According to theprevious methods of regulation, when a constant current is required to be delivered through a line, it has been necessary to dependupon the magnetic supersatu- .ration of the core of the induction'coil by the primary current, which necessitatesan expenditure of some fifty per cent. of the available electric energy in an extra field of force. By the system hereinbefore described, a given percentage of useful effect may be obtained throughout the entire range of working, as the loss arising from imperfect regulation is comparatively unimportant.

I claim as my invention 1. The combination, substantially as hereinbefore set forth, of a source of electricity, a circuit therefor, translating devices operated by electric energy derived from said source, and an electromagnetic device consisting of a mass of inductive material and opposing coils of wire applied thereto included in said circuit, varying the counter electro-motive force established in said circuit in an inverse proportion to the number of translating devices in operation. 7

2. The combination, substantially as here inbefore set forth, of a source of electricity, a circuit supplied by said source of electricity, an electromagnetic device consisting of a mass of inductive material and coils of insulated wire applied thereto included in said circuit and establishing a variable counter electro-motive force therein, an inductorium having its primary coil connected with said source, and translating devices included in its secondary circuit.

3. The combination, substantially as hereinbefore set forth, of a source of electricity, a circuit supplied by said source of electricity, an inductorium having its primary coil connected with said source, a secondary circuit for the same having a variable resistance, and an inductive device for establishing a counter electro-motive force in said circuit, and thereby modifying the strength of current traversing the primary coil in inverse proportion to the changes in the resistance of the secondary circuit.

4. The combination, substantially as here inbefore set forth, of a source of electricit a circuit supplied by said source of electricity, two opposing coils included in' said circuit, a core under the influence of said coils, a shunt for one of said coils, and an inductorium having its primary coil included in said shunt.

5. The combination, substantially as hereinbefore set forth, of a source of electricity, a circuit supplied by said source of electricity, two opposing magnetizing coils included therein, a core of soft'iron under theinfluence of said opposing coils, a shunt-circuit around one of said opposing coils, an inductorium having its primary circuit included in said shunt, and translating devices included in circuit with the secondary coils.

6. The combination, substantially as hereinbefore set forth, with an electric circuit, of an induction-coil having its primary coil in said circuit, a circuit for the secondary coil, means for varying the resistance of the secondary circuit, a soft-iron core, and two opposing coils acting thereupon, one of which coils is included between the terminals of the primary coil. 1

7. The combination, substantially as hereinbefore set forth, of an electric generator or other source of electricity, a circuit therefor, means for automatically regulating the current produced thereby, two opposing helices included in said circuit, a core under the influence of said coils, a shunt-circuit around IIO . one of said coils, an inductorium having its 7 primary coil included in said shunt, translating devices included in the secondary eir cuit of the inductorium in multiple are, and means for cutting the same in and out of circuit.

S. The combination. substantially as hereinbei'ore set forth, with a source of alternating or intermittent electric currents and a circuit therefor, of a converter included in said circuit, translating devices in the secondary circuit ol' the converter, a magnetizing-coil included in circuit with said converter, a second coil forming a shunt around the converter, and a mass of soft iron acted upon oppositely by electric currents traversing said coils;

In testimony whereof I have hereunto suhscribed my name this 9th day of November, A. D. 1885.

WVILLIAM STANLEY, JR.

Vitnesses:

DANL. W. EDG-ECOMB, CHARLES A. TERRY. 

